520 ALASKA 2020 SECTION 726
726-2.01 TOPSOIL. Furnish a natural friable surface soil without admixtures of undesirable
subsoil, refuse, or foreign materials. Meet the following:
1.Reasonably free of litter and free from roots, clods, hard clay, prohibited noxious weeds, tall grass, brush, sticks, stubble, and be free- draining and non- toxic. Prohibited and Restricted Noxious Weeds are listed in 11AAC 34.020 is located at the following URL: http://plants.alaska.gov/invasives/noxious -weeds.htm .
2.Contain between 3 percent and 20 percent organic matter as determined by loss -on-ignition of oven dried samples according to ATM 203.
3.Grading requirements: Notify the Engineer of the source of topsoil at least 30 days prior to delivery of topsoil to the project from that location. The Engineer will inspect and test the topsoil and its source before approval will be granted for its use. Unsuitable topsoil sources may be used if, prior to delivery to the project, sufficient organic matter in the form of pulverized peat moss or rich organic soil from other sources is thoroughly mixed with the topsoil to provide a product meeting the above requirements. Use the application rates, determined by the Engineer, of fertilizer and limestone per acre of ground area of topsoil, based on soil analysis tests so that the total natural and applied c hemical constituents are as follows: Nitrogen 45 - 65 pounds per acre Phosphoric Acid 45 - 90 pounds per acre Potassium 45 - 90 pounds per acre TABLE 726 -1 LIMESTONE REQUIREMEN TS Soil pH Limestone, tons/acre Above 6.0 0 5.0-6.0 1.5 Below 5.0 3.0 Sieve Percent Passing 2 in. 100 No. 4 75-100 No. 10 60-100 No. 200 10-70 521 ALASKA 2020 SECTION 727 SOIL STABILIZATION M ATERIAL
727-2.01 MULCH. Use one of the following:
1.Wood Cellulose Fiber or Natural Wood Fiber . Processed wood fiber with the following characteristics:
a.Contains no germination- or growth -inhibiting factors.
b.Will remain in un iform suspension in water under agitation and will blend with grass seed, fertilizer and other additives to form a homogeneous slurry.
c.Will form a blotter -like ground cover on application, having moisture absorption and percolation properties and the abil ity to cover and hold grass seed in contact with soil.
d.Dyed a suitable color to facilitate inspection of its placement.
2.Ship the mulch material in packages of uniform weight (plus or minus 5 percent) and bearing the name of the manufacturer and the air -dry weight content.
3.Use a commercial tackifier on all slopes steeper than 2:1. Use the amount recommended by the manufacturer.
4.Dried Peat Moss . Partially decomposed fibrous or cellular stems and leaves of any of several species of Sphagnum mosses with the fol lowing characteristics:
a.Chopped or shredded to allow distribution through normal hydraulic type seeding equipment and capable of being suspended in water to form part of a homogeneous slurry.
b.Free from woody substances and mineral matter such as sulfur or iron and with a pH value of between 4.0 and 6.5.
c.Furnished in an air dry condition and contain less than 35 percent moisture by weight. Have a water holding capacity of not less than 800 percent by weight on an oven dry basis.
d.Non- toxic.
727-2.02 MATTING . Use one of the following:
1.Burlap. Standard weave with a weight of 3.5 to 10 oz/ yd2.
2.Jute Mesh Fabric . Cloth of a uniform, open, plain weave of undyed and unbleached single jute yarn. Use yarn that is loosely twisted and not varying in thickness more than one- half its normal diameter. Furnish jute mesh in rolled strips meeting the following requirements:
a.Width: 45 to 48 inches, ± 1 inch
b.78 warp- ends per width of cloth (minimum)
c.41 weft -ends per yard (minimum)
d.Weight: 20 ounces per linear yard, ± 5%
3.Woven Paper or Sisal Mesh Netting. Woven from twisted yarns available in rolls 45 to 48 inches wide. Mesh may vary from closed to open weave, ranging from 1/8 to 1/4 inch openings. Shrinkage after wetting may not exceed 20 percent of the surface area.
Source: Alaska Standard Specifications for Highway Construction, 2020 Edition. Pages 548–548 of 584.